<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box {
            width: 100px;
            height: 100px;
            background-color: rgb(180, 28, 175);
            margin: 0 auto;
            /* 这四个数值分别是：水平偏移量、垂直偏移量、模糊度、阴影的颜色 */
            box-shadow: 10px 10px 10px rgba(0, 0, 0, 0.5); /* 阴影效果 */
        }
    </style>
</head>
<body>
    <div class="box"></div>
</body>
</html>